Make a AAA spaceholder/dummy cell

Just a quick tutorial on how to make a AAA dummy cell with a Harbo Freight spring. This came about as I was running out of dummy cells from making pen lasers.

They can be found here (item #67582)
200 Piece Assorted Spring Set



I have tons of springs from buying packages of them. I took out the ones that were not tightly wound and have them in a different spot so here's the rest:


Pulled out the ones to use:



There's too much solder paste on this one but you get the idea. Put a bit of paste on the end:


Melt some solder until it drops into a blob and quicky set the spring end on it and then just add solder as you need to to solder across making one end flat and the other a bit taller:


I made 10 of them:


After a bit of cleanup and then shaping as I wanted to with a dremel:


Put 3 layers of heat-shrink tubing on heating them one at a time:


Tada:

Hi ,Pman,
When i make a 10440 dummy cell which is the same diameter as a AAA cell. I went to Home depot and bought a 1/4 Inch AL rod and applied 2 pieces of electrical tape on them and trimmed the ends. Works awesome in my single cell pens and builds solid contact no soldering. And they look good to .... I never would have thought about using springs for dummies .. good move..

Rich

Needed something to do and I obviously have a ton of springs, solder and heat-shrink tubing. I'll take a look next time I'm driving by there. I like using heat-shrink as there's no risk of tape glue on anything and it comes out really clean looking. Those spring sets are great as they have some springs you can use that are a bit stiffer than the normal module ones that sometimes make the lens be too loose and I don't like using Teflon tape as it likes to come apart when turned on and can potentially get between the diode and lens. Every single time someone has sent me a laser that has the Teflon tape on the lens it has had to be removed because it is doing just that. There's also some nice smaller springs for adding to fasttech 532nm modules for the negative at the end of the driver or for a contact board.
Hey, why don't you give the link to that stuff here and add a pic. I'm always down for sharing building techniques. Sounds like that would be a great choice depending upon how expensive a rod is. I always just bought my AA and AAA place holders (that's what fasttech calls them) from Fasttech but the one thing I don't like about them is they are very light and when you use the springs or I'm sure your way it adds a quality heft to the build. I might go through my stuff and replace all the fasttech ones with the ones I build as I can always make more.
By the way, the list of pens that I have completed is in my pen thread and I should be finishing a couple more by the end of the weekend if the parts come. I had an issue with a 638nm 120 diode blowing on me somehow and the replacement is on its way. Not sure what happened as it should not have blown. Only thing I can come up with was it was a weak diode because Jordan states they can take a lot of abuse. We shall see. I'll eventually post them all but I've been busy with other stuff.

Just looked and that AL rod is really cheap. Good find I see it is even cheaper at Lowes.

Hi P,
where did you get the heat shrink in that size/ i'll use that instead of tape awesome Going to test some 660nm saturday morning for efficiency have 5 diodes for some builds and some single mode 520's and 450's coming soon. And those springs for the lens i'm going that way for more tension no teflon..

rich

Whauu nice work :bowdown:

No wonder my local Harbor Freight has no springs left Cornyness aside they look just like the yellow dummies I got with that heat shrink. Its also not a bad idea to make a few to practice some soldering skills. Iv'e made some from 1/8 AL rod with tape like lifetime, made them with paper clips, broken toaster oven metal grate, and the broken clocks numbers hand but the Al on these is so thin I wouldnt risk on a high amp. Anyway all builds of these are good to know.

This is a pretty awesome idea. +rep if I can... but I can't yet...

Was waiting for the mail to arrive and made another 10 as I started replacing the light dummy cells with them. Didn't get a chance to check out lowes or home Depot yet for the rods.

Pman said:

Was waiting for the mail to arrive and made another 10 as I started replacing the light dummy cells with them. Didn't get a chance to check out lowes or home Depot yet for the rods.

Click to expand...

As far as higher currant and amps is there any draw backs to those dummy cells? They are quite light:undecided:

Silly question: what are dummy batteries good for?